In the manufacture of semiconductor chips a silicon wafer or other substrate is exposed to a variety of different processes in different processing chambers. The chambers may expose the wafer to plasmas, chemical vapors, metals, laser etching, and various deposition and acid etching processes in order to form circuitry and other structures on the wafer. During these processes, the silicon wafer may be held in place by a vacuum chuck or an electrostatic chuck (ESC). The chuck holds the wafer by generating an electrostatic field to clamp the back side of the wafer to a flat surface or puck surface of the chuck.
As fabrication techniques for plasma processing equipment advance, such as those designed to perform plasma etching of microelectronic devices and the like, the temperature of the wafer during processing becomes more important. Liquid cooling is sometimes used to absorb the plasma power heat and remove it from the chuck. In some cases, other processes are performed at much lower temperatures than a typical plasma process. A chuck that operates under a wide range of temperatures allows different processes to be performed without moving the wafer to a different holder. This allows for reduced costs for the fabrication as a whole.
For lower temperature processing operations, condensation may occur on the processing equipment. When it occurs on a wafer or other substrate holder, such as a pedestal, carrier, or chuck, condensation can impair the operation of the holder. It can also reduce the operational lifespan of the holder.